Liquid crystal display devices are used not only in watches and electronic calculators, but also in various measurement instruments, panels for vehicles, word processors, electronic organizers, printers, computers, televisions, clocks and advertising display boards and the like. Representative examples of the liquid crystal display method include the TN (twisted nematic) method, the STN (super twisted nematic) method, and methods using TFT (thin film transistor) such as the vertical alignment method and the IPS (in-plane switching) method. The liquid crystal compositions used in these liquid crystal display devices require good stability relative to external stimuli such as moisture, air, heat and light, must exhibit a liquid crystal phase across as broad a temperature range as possible, centered about room temperature, and also require low viscosity and a low drive voltage. Moreover, in order to ensure optimal values for the dielectric anisotropy (Δ∈) and the refractive index anisotropy (Δn) and the like for various display devices, the liquid crystal composition is typically composed of several compounds through to several tens of compounds.
In horizontal alignment displays such as TN, STN and IPS (in-plane switching) displays, a liquid crystal composition having a positive Δ∈ value is used. Further, a drive method has been reported in which a liquid crystal composition having a positive Δ∈ value is aligned vertically when no voltage is applied, and display is achieved by applying a horizontal electric field, and therefore the demand for liquid crystal compositions having a positive Δ∈ value is growing.
Furthermore, these drive methods require low-voltage driving, high-speed response, and a broad operating temperature range. In other words, a positive Δ∈ with a large absolute value, a low viscosity (η), and a high nematic phase-isotropic liquid phase transition temperature (Tni) are required. Further, from the viewpoint of setting the value of the product regarding Δn and the cell gap (d), namely Δn×d, the value of Δn for the liquid crystal composition must be adjusted to an appropriate range in accordance with the cell gap. In addition, when the liquid crystal display device is used in a television or the like, a high-speed response is particularly important, and therefore a liquid crystal composition having a small rotational viscosity (γ1) is required.
Examples of compositions that have been disclosed as liquid crystal compositions include liquid crystal compositions containing a compound represented by formula (A-1a) or (A-1b) shown below and a compound represented by one of formulas (B-1a) to (B-1c) shown below (see Patent Document 1), and

liquid compositions containing a compound represented by formula (A-3) shown below, a compound represented by formula (A-2a) or (A-2b) shown below, and a compound represented by formula (B-2a) shown below (see Patent Document 2).

Features of these liquid crystal compositions include the fact that the cyclic structure of the liquid crystal compound having a positive Δ∈ value contains 3 rings and includes a —CF2O— structure as a linking group.
On the other hand, as the number of applications for liquid crystal display devices continues to expand, large changes are being seen in the methods of using liquid crystal display devices, and the methods of producing these devices. In order to cope with these changes, properties other than the conventionally known basic physical properties now require optimization. In other words, the VA type, IPS type and the like are now widely used in liquid crystal display devices that use liquid crystal compositions, and extremely large display devices of 50 inches or more are now being used in practical applications. As the substrate size has increased, the method used for injecting the liquid crystal composition onto the substrate has also changed, with the predominant injection method changing from the conventional vacuum injection method to the one drop fill (ODF) method, but a problem has arisen in that dropping mark defects which occur when the liquid crystal composition is dropped onto the substrate can cause a deterioration in the display quality.
Moreover, in a liquid crystal display device production process using the ODF method, the liquid crystal must be dropped in an injection volume optimized for the size of the liquid crystal display device. If this injection volume varies significantly from the optimal value, then the balance between the preset refractive index and the drive electric field for the liquid crystal display device collapses, and display defects such as spot formation or contrast faults tend to occur.
Particularly in the case of small liquid crystal display devices such as those used widely in popular smart phones, because the optimal liquid crystal injection volume is small, controlling the variation in volume from the optimal value within a specific range is difficult.
Accordingly, in order to maintain a high yield for the liquid crystal display device, the liquid crystal composition must be minimally affected by the sudden pressure changes and impacts that occur inside the dropping apparatus when the liquid crystal is being dropped, and must be able to be dropped continuously in a stable manner over a long period of time.
In this manner, in the field of liquid crystal compositions for use in active matrix driven liquid crystal display devices driven by TFT devices or the like, not only the properties conventionally regarded as important for liquid crystal displays such as a high specific resistance value or high voltage holding rate, and good stability relative to external stimuli such as light and heat be realized, but also the development of liquid crystal compositions which consider the method used for producing the liquid crystal display device while maintaining the properties and performance required of liquid crystal displays such as high-speed response performance are now being demanded.